What should be the presentation of $\mathbb Z$?

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In the Dummit-Foote text the definition of relation and presentation (Group theory) are introduced as: enter image description here

In connection with the above definition I wounder what should be the presentation of $\mathbb Z$? Clearly enough here the generating set $S=\{1\}.$ But I'm clueless about the set of equation(s) $R_i$ in $\{1,0\}$ so that $\mathbb Z$ can be presented as:

$$\mathbb Z=\langle 1:R_i\rangle$$

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$\mathbb Z$ is the free group on one generator - free groups have generators but no relations. You could say that the set of relations is empty.

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$\mathbb Z$ is a free group with one generator. So $\mathbb Z$ has a single generator without any relation. In the formulation of Dummit-Foote, $m = 0$ and $$\mathbb Z = \langle \{a\} \mid \ \rangle.$$

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It's just $\mathbb{Z}=\langle z \mid \emptyset\rangle$